经理想知道周末每天卖出多少个座位。从 tickets 表里按 day 分组，每组一行：第一列 day，第二列这一天的 seats 加起来。
| id | title | genre | minutes | rating |
|---|---|---|---|---|
| 1 | Robot Summer | family | 95 | 8 |
| 2 | Dark Lake | horror | 110 | 6 |
| 3 | Space Pals | family | 88 | 7 |
| 4 | The Long Road | drama | 142 | 9 |
| 5 | Laugh Track | comedy | 101 | 5 |
| 6 | Snow Day | comedy | 92 | 7 |
| id | movie_id | day | seats | price |
|---|---|---|---|---|
| 1 | 1 | Fri | 2 | 40 |
| 2 | 1 | Sat | 4 | 80 |
| 3 | 2 | Fri | 1 | 25 |
| 4 | 3 | Sat | 3 | 54 |
| 5 | 4 | Sun | 2 | 60 |
| 6 | 1 | Sun | 1 | 20 |
| 7 | 5 | Sat | 2 | 36 |
| 8 | 3 | Sun | 5 | 90 |
| id | title | genre | minutes | rating |
|---|---|---|---|---|
| 1 | Robot Summer | family | 95 | 8 |
| 2 | Dark Lake | horror | 110 | 6 |
| 3 | Space Pals | family | 88 | 7 |
| 4 | The Long Road | drama | 142 | 9 |
| 5 | Laugh Track | comedy | 101 | 5 |
| 6 | Snow Day | comedy | 92 | 7 |
| id | movie_id | day | seats | price |
|---|---|---|---|---|
| 1 | 1 | Fri | 2 | 40 |
| 2 | 1 | Sat | 4 | 80 |
| 3 | 2 | Fri | 1 | 25 |
| 4 | 3 | Sat | 3 | 54 |
| 5 | 4 | Sun | 2 | 60 |
| 6 | 1 | Sun | 1 | 20 |
| 7 | 5 | Sat | 2 | 36 |
| 8 | 3 | Sun | 5 | 90 |
-- 在这里写：第二列改成 SUM(seats)，再按 day 分组 SELECT day, seats FROM tickets;
写好了先点「运行」看看结果，没问题再点「提交」。